Use JDK 17 for Gradle

The binaries will still be compiled for JDK 8 but the JDK that runs Gradle will be 17.

Author: SmushyTaco

.github/workflows/release.yml

@@ -18,11 +18,11 @@ jobs:
         run: |
           git config user.name "Zonky Bot"
           git config user.email "[email protected]"
-      - name: Set up JDK 8
+      - name: Set up JDK 17
         uses: actions/setup-java@v5
         with:
           distribution: 'zulu'
-          java-version: '8'
+          java-version: '17'
           cache: 'gradle'
       - name: Make Gradle wrapper executable
         run: chmod +x gradlew

.github/workflows/test.yml

@@ -6,7 +6,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        java: [8, 11, 17, 21, 25] # LTS and newer versions
+        java: [17, 21, 25] # LTS and newer versions
     steps:
       - name: Checkout project
         uses: actions/checkout@v5